WO2018215632A1

WO2018215632A1 - Disk brake and brake actuation mechanism

Info

Publication number: WO2018215632A1
Application number: PCT/EP2018/063739
Authority: WO
Inventors: Stefan Sandberg
Original assignee: Haldex Brake Products Ab
Priority date: 2017-05-26
Filing date: 2018-05-24
Publication date: 2018-11-29
Also published as: CN110914572B; DE202017002779U1; CN110914572A

Abstract

The invention relates to a brake actuation mechanism for a disc brake, comprising an adjusting device (B) that can be rotated on a rod (1) and is axially displaceably guided at least in parts. The invention also relates to a disk brake comprising said type of brake actuation mechanism.

Description

Disc brake and brake actuation mechanism

The present invention relates to a

Brake actuation mechanism for a disc brake and a

Disc brake, in particular for commercial vehicles, having such a brake actuation mechanism.

In this case, the invention comprises disc brakes which have either a sliding caliper or a fixed caliper, and which engage over one or more brake discs. The invention relates primarily, but not exclusively, to partially coated disc brakes.

Disc brakes, especially for heavy trucks, are known in a variety of embodiments, both in terms of the type of brake actuation mechanism, the manner of transmitting the braking force to one or more discs and the nature of the adjustment to compensate for wear of the brake pads.

A special embodiment of a

Brake actuator, which is used in disc brakes, is known for example from the international application WO 2011/113554 A2 of the applicant. The known from this application brake actuation mechanism is characterized by an extremely compact design, which is associated with a smaller footprint in the housing of the caliper and with a lower weight. All components of this brake actuation mechanism are functionally cooperatively mounted in the caliper by means of a rod mounted in the housing of the caliper in the axial direction so as to be parallel to the axis of rotation of the brake disc Act. As a result of a displacement movement of the

Reinforcing mechanism performs a pressure element together with an adjusting a translational movement in the direction of the brake disc in order to transmit the clamping force.

The adjusting device for the compensation of wear has a torque clutch, which is torque-controlled and the selective transmission of a rotational direction-dependent rotation between components of the torque clutch is used. In addition, the adjusting device still has a one-way clutch, in which two rotatably mounted on the rod elements, an inner receiving sleeve and a hollow shaft are interconnected by means of a freewheeling spring, wherein the one-way clutch is designed so that it during a brake actuation rotational movement between the transmits both elements while slipping on brake release. For exact operation in terms of delivery and transmission of the braking force and the Nachstellbewegung in the known from the prior art

Brake actuation mechanism is hereby expressly referred to the disclosure content of WO 2011/113554 A2. Further, similarly designed brake actuation mechanisms are known, for example, from WO 2013/083857 A2, WO 2014/106672 A2 or WO 2015/140225 A2 of the Applicant, to which reference is likewise expressly made. When changing worn brake linings, at least the adjusting device of the

Bremsbetätigungsmechanismus, but usually the entire mechanism are reset to disassemble or decouple the brake pads or the brake pad holder plates of the pressure piece of the pressure element. For this purpose, a gear is provided in the prior art, which is arranged on the brake disc side facing away radially on the outside of the adjusting spindle and connected to this torque transmitting. The gear is rotated by a separate actuatable from outside of the caliper mechanism to move the adjusting spindle back, so to draw into the interior of the housing of the caliper. In this context, reference is made by way of example to the illustrations of FIGS. 5 and 11 and the associated description points of the above-mentioned WO 2011/113554 A2.

In the different embodiments of the prior art described above, the gear is in an immediate, the clamping force transmitted contact with a bearing seat body of the lever, so that the clamping force is introduced via the gear axially into the adjusting spindle. Based on this, the invention has the object to provide a further developed brake actuation mechanism in which the gear for the provision of the adjusting device is decoupled in the operating state from the power flow of the clamping force for purposes of pad replacement. In addition, an object is to provide a disc brake in which such brake actuation mechanisms are used.

These objects are achieved with a brake actuation mechanism according to claim 1 and with a disc brake having such a brake actuation mechanism according to claim 9.

The gist of the present invention is a disc brake brake actuation mechanism to provide, comprising

a reinforcing mechanism for introducing a clamping force into a pressure member that transmits the application force to the brake disk;

- wherein the pressure element comprises a Nachstellspindel which is in threaded engagement with a pressure piece, which cooperates with a brake pad, so that a rotation of the adjusting spindle leads to an axial displacement of the pressure piece;

- an adjusting device, which is designed to enable the adjusting spindle to compensate for a lining wear during an operating state of the disc brake in rotation; and

a drive element configured to cause the adjustment spindle to rotate as needed outside an operating state of the disc brake;

wherein the drive element is decoupled from the power flow of the application force by the brake actuation mechanism. Outside of an operating state includes all circumstances in which the vehicle and thus the disc brakes of a maintenance, service or inspection are subjected.

The drive element is preferably designed as a gear which is arranged radially on the outside of the adjusting spindle.

Due to the fact that the gear during operation of the disc brake is not arranged within the force flow of the application force during brake operation, it can be made lighter overall or made of a less resistant material. At the same time thereby individual components of the

Brake actuation mechanism and thus the entire Brake actuation mechanism be made stiffer for the purpose of power transmission.

In one embodiment, the gear is received in an annular groove of the adjusting spindle.

In a preferred embodiment, the gear has a means which enters into a torque-transmitting connection with a complementary means of the adjusting spindle. Preferably, this means is formed as a radially inwardly directed projection which engages in a shape-complementary recess which is directed radially inwardly on an end side of the adjusting spindle.

Furthermore, the gear may preferably be divided in the radial direction in the region of the projection. The division allows easier mounting of the gear in the annular groove of the adjusting spindle, since the ring of the gear can be easily pulled apart.

For purposes of initiation of the application force of the reinforcing mechanism directly into the adjusting spindle, this frontally may have a radially inwardly and coaxially outwardly stepped ring, which cooperates with a shape-complementary recess of the reinforcing mechanism. In the ring itself can be provided radially inwardly more depressions, which are designed to enter into a torque-transmitting and axially displaceable connection with corresponding projections of an output element of the adjusting device.

The invention also relates to a disc brake comprising a brake actuation mechanism according to at least one of the above-described embodiments having. In particular, the invention relates to a disc brake in which a brake actuation mechanism according to at least one of the above-described embodiments by a rod in a housing of a brake caliper of the disc brake is mounted at least in modules or in total as a self-supporting unit.

Further advantages and features of the invention will become apparent from the following description of the embodiments illustrated with reference to the drawings. Show it

1 shows a lateral longitudinal section in the axial direction of a brake actuation mechanism according to the invention.

Fig. 2a is an exploded view of a part of

Brake actuation mechanism;

Fig. 2b is an exploded view of another part of the brake operating mechanism;

FIG. 3a shows a cross section along M - M from FIG. 1; FIG.

FIG. 3b shows a cross section along L - L from FIG. 1; FIG.

Fig. 4 is a perspective view of only one

Adjusting spindle of an adjusting device with a toothed wheel;

Fig. 5 is a front view of the adjusting spindle with the

Gear; and

Fig. 6 is an axial cross section through the

Adjusting spindle with the gear.

Figures 1 to 3b generally show all components of a brake actuation mechanism according to the invention. For the exact installation position of such a brake actuation mechanism according to the invention in a housing of a brake caliper reference should be made by way of example to WO 2011/113554 A2 of the Applicant, the disclosure of which is hereby incorporated by reference. The brake actuation mechanism according to the invention essentially consists of four modules which functionally cooperate, namely a reinforcement mechanism A, an adjustment device B, a pressure element C and a rear part D, the brake actuation mechanism acting as a self-supporting unit by means of a centrally located rod 1 on the latter itself and thereby is mountable in a housing of the caliper.

The reinforcing mechanism A serves a

Actuating force of a (not shown here) hydraulic, pneumatic or electro-mechanical actuator to initiate as a clamping force in the brake actuation mechanism and to reinforce according to a conditional by its construction gear ratio. A lever 2 is pivotally mounted in a rear housing portion of a (also not shown here) caliper by this is rotatably disposed relative to a roller 3, wherein the roller 3 is positioned eccentrically relative to the axis of rotation of the lever 2. Between the roller 3 and the corresponding surface of the lever 2 needle roller bearings or needle roller cages 4 are provided. At the opposite side of the roller 3, the lever 2 is pivotally mounted via corresponding needle bearings or needle bearing cages 5 in corresponding bearing surfaces of a preferably one-piece bearing seat body 6. The reinforcing mechanism A is designed so that by a rotation about the roller 3 of the lever 2 performs this against an eccentric displacement movement, which leads to a corresponding amplification of the actuating force acting on the lever 2, which then as a clamping force on one on a (not shown ) Brake disc directed Movement of the bearing seat body 6, which may be performed for this purpose in the housing of the caliper indirectly or directly linear, is transmitted to the adjusting device B and the pressure element C.

The adjusting device B follows in the axial direction with respect to the brake disc immediately following the bearing seat body 6 for the lever 2. The adjusting device B has a plurality of functionally cooperating elements.

A designed as a hollow shaft input element 7 for the adjusting device B is rotatably mounted on the rod 1. The hollow shaft 7 has a one-piece pin 8 which is received in a recess 9 in the lever 2, as shown by way of example in FIG. 4a. A pivoting movement of the lever 2 causes the input element 7 via the connection of pin 8 and recess 9 in rotation, as will be explained in more detail below in connection with FIG. 3a.

The input element 7 is connected to an output element 10 via a freewheeling spring 11, which form a first torque clutch. The output member 10 is also rotatably mounted on the rod 1 and formed as a radial bearing hub having axial longitudinal grooves 12 are guided in the ball body 13 of a ball cage 14 slidably.

In this way, it is possible that the output element 10, which is rotationally driven by the input spring 7 via the freewheeling spring 11, can transmit a rotational movement to a first, front coupling ring 15 of a second torque clutch, and yet relatively has axially displaceable to this coupling ring 15, wherein the coupling ring 15 on the inside also longitudinal grooves 12 ^λ for receiving and guiding the ball body 13 has. The second torque clutch is formed by the front clutch ring 15 via a ball bearing ring 16 with a second, rear coupling ring 17 cooperates. Here, the balls 18 are guided in the ball bearing ring 16 in corresponding, circumferentially arranged in the mutually facing end faces of both the first coupling ring 15 and the second coupling ring 17 ramps 19, as can be seen from Fig. 1, so that a corresponding torque-dependent Roller ramp mechanism is formed.

The rear coupling ring 17 transmits a rotational movement induced thereon by means of a spring-groove connection to a hollow adjusting spindle 20, for the realization of which the rear coupling ring 17 has radially projecting, uniformly distributed springs 21 in correspondingly complementary grooves 22 engage on the radial inner side of the adjusting spindle 20, as can be seen by way of example in FIG. 3b. The adjusting spindle 20 is connected via a threaded engagement with a pressure element 23 of the pressure element C, which is guided in the housing of the caliper linearly displaceable, but not rotatable, so that a rotational movement to Nachstellzwecken the adjusting spindle 20 leads to a linear displacement of the pressure element 23. As can be seen, the adjusting spindle 20 completely encloses the further components of the adjusting device B. The stamp or cup-shaped pressure piece 23 of the pressure element C acts on its front side with a (not shown here) Brake pad holder together to transfer the clamping force to the brake disc.

The application force is introduced into the pressure piece 23 by the adjusting spindle 20 is supported directly on the bearing seat body 6 of the lever 2. That The force applied by the pivoting movement of the lever 2 in the bearing seat body 6 application force is transmitted to the adjusting spindle 20 and via the threaded engagement with the pressure piece 23 and from there via the brake pad at braking engagement in the brake disc.

Furthermore, the rear coupling ring 17 is supported on the bearing seat body 6 via a low-friction thrust bearing 24. The bearing seat body 6 is with the adjusting spindle 20 directly in force-transmitting contact, wherein radially in sections encircling, axial projections 25 of the adjusting spindle 20 engage in a correspondingly shaped annular recess 26 of the bearing seat body 6. This ensures that the main force flow of the application force of the bearing seat body 6 directly into the adjusting spindle 20 and via the threaded engagement on the pressure member 23, while due to the low-friction thrust bearing 24 of the rear coupling ring 17 and thus the adjusting B as a whole largely by the clamping force in axial direction remains decoupled.

At the axial bearing 24 opposite side of the front coupling ring 15 is rotatably guided via a further friktionsarmes thrust bearing 27 to a bearing retainer 28.

At the bearing retainer 28 is a spring 29 of the rear part device D to the plant. The designed as a helical spring return spring 29 in turn is supported by the interposition of a sliding ring 30 at a Abutment shell 31 from which is attached to the brake disc facing the end of the rod 1. The return spring 29 is designed so that it exerts a defined preload on the second torque coupling, which defines the limiting transmission torque between the coupling rings.

The abutment shell 31 is in this case held by an abutment ring 32 and a fastener 33 on the rod 1 in a rotatable arrangement, as will be explained below.

In the region of the front end of the rod 1, a bearing sleeve 34 is provided, which is supported on the side facing away from the brake disc directly on the end face of the output member 10.

This bearing sleeve 34 receives a spring element 35, which in turn is supported on the abutment ring 32. In this way, according to the invention, a defined pretension is exerted by the spring element 35 via the output element 10 on the input element 7.

At the brake disc end facing the bearing sleeve 34 has a distance X to the abutment ring 32, wherein the spring element 35 passes through an opening 36 in the abutment shell 31.

It becomes clear that this makes it possible that the input element 7 and thus also the output element 10 with the bearing sleeve 34 can move in the axial direction to the brake disc by a maximum of this distance X, wherein the bearing sleeve 34 through the opening 36 in the abutment shell 31 is moved through until it comes to the abutment ring 32 to the plant. In a pivoting movement of the lever 2, the recess 9 moves in the lever 2 on a circular path forward in the direction of the brake disc. Until the upper edge of the recess 9 comes into contact with the pin 8, a game A is first bridged, which corresponds to the wear-independent clearance of the brake, which is never adjusted.

Thereafter, the recess 9 takes the pin 8 on the swivel motion corresponding circular path and so puts the input member 7 on the rod 1 in rotation.

At the same time a force is exerted on the pin 8 in the direction of the brake disc by the resulting from the orbit due to the pivoting movement of the recess 9 and the lever 2. Since the input element 7 and in principle the entire adjusting device B is mounted axially displaceably on the rod 1, the input element 7 together with the adjusting device B performs an axial forward movement on the rod 1, which is directed against the bias of the spring element 35.

This forward movement comes to an end when, after bridging the distance X, the bearing sleeve 34 comes to rest on the abutment ring 32.

Due to the fact that the pin 8 can move in addition to the rotation together with the recess 9 also by a maximum length X forward, acting in the contact point between the recess 9 and the pin 8 forces are reduced in the axial direction and the Contact friction thereby minimized, which can significantly increase the life of this device while reducing wear. According to the invention, the distance X is to be chosen so that the reduction of the forces can be carried out to a sufficient extent and at the same time the reliability of the power transmission between the lever 2 and the pin 8 is guaranteed for each state of wear for the activation of the adjusting device B.

The abutment shell 31 is coupled with the adjusting spindle 20 to transmit torque, in that a projection 37 of the abutment shell 31 is displaceably guided in an axial longitudinal groove 38 on the inner surface of the adjusting spindle 20.

Since the abutment shell 31 rotates with the adjusting spindle 20, the brake disk facing the end of the return spring 29 is decoupled via the sliding ring 30 mounted in the abutment shell 31.

The fastening element 33, which is attached to an annular groove 39 of the rod 1, and the abutment ring 32 can therefore rotate together with the abutment shell 31. According to the invention, the friction behavior between the fastening element 33 and the rod 1 in the annular groove 39 is determined in such a rotation via a corresponding dimensioning of these elements and / or determination of the surface finish in the contact surfaces, that in response to a defined counter-torque on the entire brake actuation mechanism is exercised, which is able to reduce the wear between relatively movably arranged components, especially the adjuster B.

As can be seen from Figure 1, the entire brake operating mechanism is the brake disk side by the rotatably mounted on the rod 1 fastener 33 and brake disc facing away by a mounting ring 40 on the Rod 1 held by the reinforcing mechanism A, the adjuster B, the pressure element C and the rear part D are arranged to functionally cooperate, the hollow adjusting spindle 20, the remaining components of the adjuster B and the rear part D completely absorbs. Of the

Brake operation mechanism can be mounted and fixed by means of the rod 1 as a unit in a housing of the caliper.

Figures 4 to 6 show only the combination consisting of adjusting spindle 20 and a gear 41, which serves to reset the adjusting device B when the brake pads must be replaced. It interacts with a separate, operable from outside the caliper mechanism (not shown) together.

The gear 41 is positioned on the adjusting spindle 20 with a certain axial distance Y from the bearing seat body 6, so that immediately no application force is introduced into this gear 41.

In the embodiment shown, the gear 41 is also decoupled from the output element of the second torque clutch, the rear coupling ring 17. However, it is also conceivable that this coupling ring 17 instead of directly the adjusting spindle 20 drives the gear 41 thereon and thus indirectly the adjusting spindle 20 which may have radially inwardly directed projections for this purpose, pass through the corresponding openings in the adjusting spindle 20 and the coupling ring 17 received a corresponding torque-transmitting wedge-groove connection or the like. The gear 41 is divided in the region of a radially inwardly directed projection 42 through a slot 43, which allows the gear 41 to radially pull apart for assembly purposes. The projection 42 engages torque-transmitting in a preferably complementary recess 44 in the adjusting spindle 20 a. The two halves of the projection 42 also have radial recesses 45. As a result, the gear 41 can be more easily mounted in a circumferential annular groove 46 of the adjusting spindle 20.

The bearing seat body 6 of the reinforcing mechanism A engages directly on a front-side bearing surface 47 of the adjusting spindle 20, wherein the gear 41 is decoupled from the force applied via this bearing surface 47 Zuspannkraft by the distance Y.

Claims

claims

Brake actuation mechanism for a disc brake

- With a reinforcing mechanism (A) for introducing a clamping force in a pressure element (C), the

Applying clamping force to the brake disc;

wherein the pressure element (C) has a night setting spindle (20) which is in a threaded engagement with a pressure piece (23) which cooperates with a brake pad, so that a rotation of the adjusting spindle (20) leads to an axial displacement of the pressure piece (23). leads;

- With an adjusting device (B), which is designed, during an operating state of the disc brake, the adjusting spindle (20) to compensate for a

To turn lining wear in rotation; and

- With a drive element (41) which is configured to enable the adjusting spindle (20), if necessary, in rotation outside of an operating state of the disc brake; characterized in that

the drive element (41) is decoupled from the power flow of the application force by the brake actuation mechanism.

Brake actuation mechanism according to claim 1, wherein the drive element is designed as a toothed wheel (41) which is radially outwardly on the adjusting spindle (20).

is arranged.

A brake operating mechanism according to claim 2, wherein the gear (41) is received in an annular groove (46) of the adjusting spindle (20). A brake operating mechanism according to claim 2 or 3, wherein the gear (41) comprises means (42) provided with a means (44) of the adjusting spindle (20)

enters torque-transmitting connection.

A brake actuation mechanism according to claim 4, wherein the means (41) is a radially inwardly directed one

Projection is formed, which engages in a shape-complementary recess (44).

A brake operating mechanism according to claim 5, wherein said gear (41) is divided in the radial direction.

Brake - actuating mechanism according to one of the preceding claims, in which the adjusting spindle (20) has at least one ring element (25) which is offset radially inwards and coaxially outwards and which has a complementary shape (26) of the recess

Reinforcement mechanism (A) cooperates.

Brake actuation mechanism according to claim 7, wherein in the ring element (25) radially inwardly more recesses

(22) are provided, which are designed to with corresponding projections (21) of an output element

(17) the adjusting device (B) a

torque transmitting and axially displaceable

To connect.

Disc brake having one

Brake actuation mechanism according to at least one of claims 1 to 8.

Disc brake according to claim 9, wherein the

Brake actuation mechanism according to at least one of claims 1 to 8 by a rod (1) in a housing a caliper of the disc brake is mountable as a self-supporting unit.